This invention relates generally to the on line measurement of three dimensional objects, in particular, golf ball components.
One of the critical features of golf ball construction is the xe2x80x9croundnessxe2x80x9d or xe2x80x9ctruenessxe2x80x9d of the various components comprising a golf ball, such as centers, cores, and the ball itself. It is critical that the dimensions of the balls, cores, and centers are equal in all axes and planes.
Common methods of measuring dimensions of golf balls and golf ball components are offline, bench-type instruments. One example of such an instrument currently in use is a strain gauge-type instrument. This instrument allows manufacturers to sample the dimensions of a few golf balls, cores, and centers from a large quantity, to verify that the dimensions are of the correct magnitude. The strain gauge instrument encompasses a series of pins and calipers that are translated towards a ball disposed between them. Once each pin touches the surface of the ball, the distance each pin has traveled is compared to the distance it should have traveled, assuming an ideally-constructed object. This, and other offline/bench methods, are slow, measure very few data points, and are generally limited to measuring dimensions at a single axis or plane of the ball.
This type of measuring, while accurate, fails to completely measure the entire ball. When dealing with a spherical object, there are effectively, an infinite number of axes or planes through which a diameter, for example, could be measured. If a series of pins/calipers are translated to touch a spherical surface, one is limited to one axes/plane per two pins. As with any spherical object, such as a golf ball, the diameter might be identical for a number of planes and different for another plane, not measured. This out-of-round plane creates a problem, particularly in the golf ball industry, for obvious reasons.
Not only is a method needed for measuring a large number of planes/axes of golf balls and golf ball components, one that allows sampling of the maximum number of balls is even more preferred. Simply selecting a few golf balls from a large sample allows for a large margin of error. There is thus a need for a fast, online measuring method that measures a plurality of axes of a golf ball.
The present invention is directed to a method for monitoring a spherical object such as a golf ball or a golf ball core, by providing a measuring field in which the spherical objects are fed into while being rotated as they translate in the field. A laser generating emitter and receiver determine the size of the field in which the center of a continuous wave laser beam intersects with the center of the core. The spheres rotate in a forward direction as they translate forward by gravity on a pair of rails. Simultaneously, they are subjected to a perpendicular rotation that is caused by the turning of the rails. The resultant action upon the spheres provides for a plurality of diameters to be measured and the resulting data fed to a controller for Quality Control analysis.
An embodiment of the invention would have a plurality of vision cameras that would be in addition to or in lieu of the laser generating equipment. The cameras would be oriented perpendicular to the axis of translation of the spheres and would take photo-images of the rotating spheres on CCD or other type photo detectors. The images would be sent to a controller for processing.
The present invention provides for a mechanism that includes a track having rotating rails, whereby the spheres are rotated in a generally perpendicular rotation to the inherent rolling direction as they translate through the measuring field. The means for translating them through the field can be any conventional usage such as gravity or use of an augur to spirally feed the spheres into the field. Each sphere will have about 100 to 200 different diameter planes measured as it moves through the measurement field.